php - 添加两个 mysql 列并返回总计时遇到问题

Question

我正在尝试添加 mysql 列，然后将列总数返回到 php 页面。我的代码可以工作，但它没有返回值:

<?
$pointresults2 = $dbh->prepare("SELECT sum(features + contributions + likes 
)   
AS total FROM points WHERE (ID = :user_ID)");
$pointresults->bindParam(':user_ID', $user_ID, PDO::PARAM_INT); 
$pointresults2->execute();
$pointrow2 = $pointresults2->fetchAll(PDO::FETCH_ASSOC);
?>

<h3><b>Points TEST: <?php echo $pointrow2[0]['total'] ?></b></h3>

Answer 1

您的情况没有功能、贡献、点赞。此外，您还提供了错误的名称作为参数user_ID。

<?php
$stmt = $dbh->prepare("SELECT sum(features + contributions + likes) AS total FROM points WHERE (ID = :user_ID)");
$stmt->bindParam(':user_ID', $user_ID, PDO::PARAM_INT); 
$stmt->execute();
$row = $stmt->fetch(PDO::FETCH_ASSOC);

echo '<h3>'. $user_ID .' have '. $row['total'] .' Points.</h3>';
?>